So three years ago, it instituted an annual end-of-summer-vacation "free day," during which the museum throws open its doors to anyone who wishes to visit.

The fourth annual "Summer's Last Roar" is slated for Saturday, Aug. 25, and will offer activities in conjunction with the museum's current exhibition, "Big Food: Health, Culture and the Evolution of Eating."

"Our free day this year focuses on nutrition, exercise and general well-being," Brigockas wrote in an email.

" `Big Food' is really the focus of this event and an opportunity for visitors to learn from it, especially those for whom paid admission is a hardship. It could really save lives if more people saw it.

"We hear that kids are quoting parts of the exhibit to their family and friends ... This is a chance for everyone to attend without cost being a deterrent," she wrote.

Local organizations will participate and many will distribute free informational brochures on the benefits of healthy foods and exercise. Featured offerings, according to Brigockas, will include the following.

The Hispanic Health Council will present two puppet shows with Felipe Munoz, nutrition educator, as puppeteer. "Tommy Enjoys Exercise" will be presented at 11 a.m.; "Five Food Groups" will follow at noon. The council also will hand out information on nutrition, diabetes prevention, physical activity and well-being. Bi-lingual educators will be on hand to answer questions and provide information for parents and teachers.

The Yale Rudd Center for Food Policy and Obesity will distribute DVDs on weight-based bullying and host a Jeopardy-type game, in which visitors can test their knowledge of different types of food. Educators will be available to answer questions and pass out literature on weight bias in school and social settings.

According to Brigockas, "Big Food" presents a life-changing look at our eating habits and how they have evolved. Food tastings and an instant-winner game will be among the offerings in the exhibit galleries.

"The exhibit addresses dangerous trends in food choices and food consumption -- for instance, food portions are more than 50 percent larger than in the 1930s -- and the corresponding increase in obesity rates and decrease in physical activity.

"Near the end of the exhibit there is a place for visitors to vote on what action they intend to take toward a healthier lifestyle. Options include eating meals together as a family, exercising more, drinking fewer sugary drinks and supporting community involvement and policy change to make food and drink in schools and on store shelves healthier from the start," she said.

"There are a couple of fun, interactive games that interest both kids and adults," she added.

"One involves balancing the food you eat with exercise; the other is guessing the amount of sugar, fat and salt in certain popular foods, then comparing your answers with the computer's data," she explained.

In the "Liquid Candy" display, the number of spoonfuls of added sugar in bottled and canned drinks, many of which we think of as healthful alternatives of soda, is featured.

And of course, everyone is invited, she said, to visit the entire museum, including the Great Hall of Dinosaurs, in which a 70-foot-long, 150-million-year-old Apatosaurus is awesome, along with Rudolph Zallinger's Pulitzer Prize-winning mural, "The Age of Reptiles." (At 110 feet long and spanning 300 million years of dinosaur history, the mural is considered the world's largest and most famous dinosaur painting.)

Free parking will be available in the Peabody lot and adjacent Yale lots throughout the day.